Many years ago, someone produced an actual rank order of plane lethalities based on data that included muzzle velocities, ballistics, rates of fire, calibers, ammo loads, number of guns, etc. I don't remember who that was (Dinger maybe?), but it's pretty silly to argue subjective lethality when there's actual information out there that can show the relative lethality of German planes to British planes.
If I recall, they're closer than you think.